1. Field
The following description relates to a robot for inspection of pipeline using a multi-output differential module, and more particularly, to a robot for inspection of a pipeline using a multi-output differential module provided in the robot to distribute a driving power transmitted to a plurality of proceeding units.
2. Description of Related Art
Generally, a pipeline that is one of the structures of an industrial infrastructure facility is a representative facility for transferring various energy resources such as gas/petroleum and the like and for evenly distributing the energy resources in right places.
These various kinds of pipelines are distributed here and there nationwide just like blood vessels in a human body, and are being settled as core infrastructure facilities that supply relentless amount of energy resources such as gas/petroleum and the like to various urban infrastructure facilities and plant facilities. Furthermore, pipelines in large-scale plants such as petrochemical plants are being used as main facilities for transferring various chemical materials to be refined and processed.
However, after a certain period of time passes since installing a facility, pipelines may be damaged due to corrosion caused by moisture and various chemical materials, and effects from external environments, and damaged pipelines may cause leakage of internal materials to outside, which is a problem.
Leakage of petroleum and chemical materials may cause serious environmental pollution, and leakage of gas may cause massive gas explosion accidents and the like. Therefore, pipelines need to be inspected and replaced on a regular basis when a certain period of time has passed.
Pipelines may be classified into two types depending on the shape of installation: broad type pipelines and dense type pipelines. The broad type pipelines are mainly used for water supply/sewerage pipelines, gas supply pipelines, petroleum supply pipelines, and the like mostly in urban and national infrastructure facilities. These types of pipelines are usually laid underground for damage protection from outside, urban landscape maintenance, and anti-corrosion and the like, but a disadvantage of these types of pipelines is that the pipelines must be taken out every time it needs to be repaired or inspected.
The dense type pipelines are mainly used for plants such as petrochemical factories, and various types of pipelines are usually tangled to one another due to complicated transfer systems, and in many cases, there are path divergent areas (for example, divergent ducts). However, a disadvantage of this type of pipelines is that in the case where a dense type pipeline positioned in an interior area needs to be inspected, the pipelines in exterior areas of that pipeline all need to be removed. Likewise, pipelines installed in high places are not easily approachable either.
Due to these reasons, there has been a need to develop an inspection equipment that could approach inside a pipeline more easily at a lower cost, and that could inspect the inside of the pipeline while moving in a manner that is suitable to the 3-dimensional shapes of the pipeline elements.
As a result, mobile robots have been developed that could thoroughly inspect inside a pipeline while driving inside the very peculiar and limited 3-dimensional space called pipeline, and much research is ongoing these days.
However, the problem with conventional pipeline inspection robots is that they have multiple proceeding wheels for turning directions according to different shapes of the pipeline, and driving units for each of the proceeding wheels so as to control the state of motion of each proceeding wheel individually, which increases the size of the robot.